A penalty in either half from Levy Madinda handed the hosts a shocking result after Pizzi and Hugo Almeida had seemingly given Paulo Bento's side control of the game
A penalty in each half - the first after a clumsy challenge from Silvio, the second following Custodio's handball - gave the hosts a share of the spoils after Pizzi and Hugo Almeida had seemingly put the Seleccao in control of the match.
Paulo Bento named a strong spine to his side, with Pepe and Joao Moutinho both starting for the visitors. In the absence of injured duo Nani and Cristiano Ronaldo, who withdrew from the squad earlier this week due to an eye injury, young Deportivo La Coruna attacker Pizzi started alongside Silvestre Varela in support of Sporting Braga striker Eder.
After something of a pedestrian opening quarter, Portugal carved out two chances in as many minutes. First Varela skipped away from Georges Ambouret and cut the ball across goal from the byline, but goalkeeper Yves Bitseki parried the ball away from danger. A moment later, Pizzi attempted a neat one-two with Moutinho, but was unable to beat Bitseki to the return ball.
The best chance of the opening half hour fell to the hosts, however, but Rogombe contrived to fire wide from point-blank range following a clever cutback from the right which dropped right into his path.
Portugal was struggling to find a rhythm on the difficult playing surface, and found itself behind after 33 minutes when Levy Madinda tucked home a confident penalty after Silvio's clumsy foul.
The lead lasted barely a minute, however, as Pizzi buried a spot kick of his own after Eder was tugged to the floor when turning his man with some clever chest control.
The half ended in controversial fashion when Beto fumbled a scuffed shot, Pepe outmuscled two Gabon attackers to hook it off the line only for the assistant referee to award a goal some 10 seconds later. With the players, coaches and fans unsure, the referee consulted with his linesman and ultimately the goal did not stand, with replays clearly showing that the ball was nowhere near crossing the line.
Bruno Alves replaced Pepe at halftime and almost became the most unlikely scorer in the freakiest of circumstances, when his looping cross confused Bitseki and ultimately came back off the crossbar.
Portugal had upped the tempo after the break and took the lead shortly before the hour mark. Varela played a superb one-two with Nelson to slice through the Gabon defense, and his scuffed shot across goal was turned home by substitute Hugo Almeida, despite the best efforts of Bitseki.
Just as Portugal seemed to be taking control, Gabon was - quite literally - handed an equalizer, when Custodio was penalized for blocking a shot with his hand, allowing Madinda to tuck home his second penalty of the night.
Pizzi came close after some brilliant control following Almeida's knockdown but he couldn't fire through the packed penalty area, before Beto made his first real save of the night as he beat out a fierce drive from Fabrice Do Marcolino.
Buoyed by their vociferous crowd, the hosts pressed on in pursuit of an unlikely winner, but no further chances were forthcoming and the sides ultimately settled for a surprise share of the spoils.